Surface solid dispersion had been established as a successful method to improve the dissolution rate and the solubility of poor soluble drugs. In the present study, the surface solid dispersion technique was applied in order to improve the dissolution rate of Irbesartan. The carriers used were microcrystalline cellulose, crospovidone, croscarmellose sodium, sodium starch glycolate, microcrystalline cellulose and potato starch. The samples were prepared at various drug-to-carrier weight ratios by co-evaporation method. The prepared

SSDs were characterized by using FTIR, Selleckchem Veliparib DSC, P-XRD, SEM and in vitro dissolution. Irbesartan (IBS) was obtained as a gift sample from Dr. Reddy’s Laboratories Ltd. (Hyderabad, India). The super disintegrants (SD) crospovidone (CP), sodium starch glycolate (SSG), potato starch (PS), croscarmellose (CC), microcrystalline cellulose (MC) and solvents used were obtained from S D Fine Chem. Ltd. The SSD of IBS and SD were prepared by solvent co-evaporation method. The required amount of IBS was dissolved in sufficient amount of methanol. The SD was dispersed in the IBS solution. The different ratios of drug and SD were shown in Table 1. The mixtures were sonicated for 15 min to ensure the intimate mixing. The solvent was then removed, using rotary vacuum evaporator at 50 °C. The residue Small Molecule Compound Library obtained was dried at 50 °C overnight. The dried mass was pulverized and passed through 80/170

mesh sieves. The products were kept in desiccators for further study. The accurately weighed amount of IBS and either SD at

1:1, 1:5 and 1:10 IBS-to-SD weight ratios were thoroughly blended by tumbling for a period of 30 min. The physical mixtures were freshly prepared prior to analysis. P-XRD patterns of the samples were recorded, using X-ray diffractometer, (RigakuMiniFlex) Advance with Cu-Kα (Ni-filter), radiation (λ = 1.5418 °A). The experiments were carried out at room temperature under the following conditions: voltage 20 kV, current 20 mA, 2θ angle range 3–60 with scanning speed 5°/min. Samples of individual components like Pure IBS, pure CP and SSD of IBS-CP combination (1:10) were weighed directly in pierced aluminum pans (5–10 mg) and scanned in the 20–200 °C temperature range under nitrogen flow of 25 mL/min with a heating rate of 10 °C/min using a DSC (Mettler Parvulin Toledo AG, Analytical, Switzerland) apparatus. FTIR–spectra of samples of individual components as well as each IBS–SD combination (1:10) were recorded in KBr medium pellets using FTIR spectrophotometer (IR affinity-1 CE, Shimadzu, Japan). The scan was performed in the range of 400–4000 cm−1. The surface morphology of samples was determined by using an analytical SEM (Hitachi S-34000N, Japan). The samples were lightly sprinkled on a double-sided adhesive tape stuck to an aluminum stub. The stubs were then coated with gold to a thickness of about 10 Å under an argon atmosphere using a gold sputter module in a high vacuum evaporator.